heat pump copper pipes vibrate and even hum

[sdowney717]

In my house these refrigerant supply pipes vibrate. If you hold with your hand, it is quite noticeable. It must be creeping up on me cause I did not notice till recently
so what is the cause of that?
It does not seem to be the air handler fan.

Could the compressor be ready to go out?
Or is it something to do with the compressor mounting?

the heat pump heats fine.

 

[rickairmedic]

Downey there are many variables that will cause the pipes to vibrate . This could be caused by the way they are mounted or lack or proper strapping . They could also be vibrating if the system is low on freon and causing a surge in the pipes . The honest truth is all pipes vibrate to some extent even your water pipes . Crazy as it sounds put your head/ear up to the pipes and see if you can hear a gurgling in the pipes this might tell you if the system is low on freon although if you have a TXV in the system this could also cause some surging sounds in the pipes . Cheap insurance would be to have a qujalified tech come out and do a system checkup on the system which should be done at least once a year anyways and really isnt usually that expensive ( unless there actually is a problem ) .

Rick

 

[redsky49]

There is also a phenomenon known as "slugging" which you may be experiencing. This is potentially very harmful to the compressor and should be corrected if it is occurring. Typically, slugging is noticed upon start-up (after the refrigerant has accumulated in the evaporator), or sometimes during the defrost cycle.

Additionally, reciprocating compressors are somewhat more susceptible to these issues than rotary types, so if you have an older R-22 recip you may want to check for flood-back or flooded start conditions.

There are several other areas to look at, though you should verify whether you are having vibration or shock, as these issues are handles differently.

As rickairmedic said, your best starting point would be to slap some gauges on the unit and take it from there.

As always, offered only as opinion

 

[sdowney717]

I actually improved this a little by securing the pipes together.
The larger pipe is covered with insulation pipe foam rubber sleeve. The smaller one is not.
I dont hear any gurgling. It vibrates all the time although to me it seems more that it ought to be. I suppose it is possible the copper pipe is touching something which amplifies the sound. It is a good 25 feet of copper between compressor and furnace. pipes go thru brick foundation, into crawl space and pass thru foundation garage wall and up into air handler. The pipes pass thru
steel pipe in the foundation wall.

It just seems this winter heating season, the sound is louder than I recall.

 

[sdowney717]

another thing this winter that happened.
When it rains or snows and it is close to freezing, The fan will build up a layer of ice on the blades. I noticed that the fan will become unbalanced and the entire heat pump will shake. I found I have to turn it off and switch to NG heat.
I wonder if that shaking did something to the compressor mounting.

Looking into the top of the heat pump you can see where ice has been slung off the blades and impacted on the inside of the coil.

The unit sits directly under the roof line. A gutter used to be there.
Water now just runs directly into the top of the heat pump.

Do you think I should put up a gutter again?
Or a rain diverter?
Or I even thought of any extension overhang to shield the top. That would sit 8 feet above the top of the heat pump. That might block air flow a little. So dont know for sure.

It runs smoothly on the outside with no obvious shake when there is no ice.
But that one ice day It was shaking pretty badly.

 

[sdowney717]

I went outside and felt the pipes on the heat pump.
The small copper pipe has no vibration.
The large one has slight vibration.

In heat mode, the liquid flow reverses, the large pipe sends it out and the small pipe is the return flow.

Inside by the furnace.
Both pipes you can feel a vibration. And the vibration seems more intense.
I do not think there is a TXV valve on the inside coil.
this is a standard Goodman setup from ~ 15 years ago.
If you put your ear on the large pipe, there is a very loud noticeable continuous vibrational hum. No slugging sounds. The hum would sort of overwhelm any other noises.

When the unit first comes on, the hum is not very noticeable, but as it continues to run, the hum seems to get more noticeable.

I do have a set of gauges.

What I can someday do, is compare that noise to a system at a friends house.